The U.K. economy has been flat for nearly two years. This stagnation has left output per capita a staggering 14 percent below its precrisis trend and 6 percent below its pre-crisis level.

Weak growth has kept unemployment high at 8.1 percent, with youth unemployment an alarming 22 percent.

The effects of a persistently weak economy and high long-term unemployment can reverberate through a country’s economy long into the future—commonly referred to by economists as hysteresis.

Our analysis of such hysteresis effects shows that the large and sustained output gap, the difference between what an economy could produce and what it is producing, raises the danger that a downturn reduces the economy’s productive capacity and permanently depresses potential GDP.